A Theology of Quantum Mechanics

How can demons possess physical creatures? How can God reach down and split the sea, or feed 5000 people with just five loaves and two fish? Is there room for a human soul or free will? In general, how does the spiritual interact with the physical? Ques­tions like these cause many to believe there is con­flict between modern science and Christianity.

With a scientific mindset, it can be difficult to rationalize spiritual interfaces with physical reality. By the end of this article, we should have at least a framework of reason in which to approach these questions. This framework builds from Alvin Plant­inga, a Christian philosopher who analyzed the re­lationship between science and Christianity.[1] In his analysis he explored how quantum mechanics can complement Christian theology. His analysis offers a perspective in which scientific principles are com­patible with spiritual interactions, thus making the claims of Christianity more plausible in a scientific context.

Quantum Mechanics Analysis

Plantinga’s discussion of QM addresses the phe­nomenon where some supernatural entity (e.g., God, angels, demons, human souls) intervenes in the physical reality. I will refer to this type of phe­nomenon simply as intervention. Plantinga argues that intervention is consistent with science when tak­ing a specific interpretation of QM into account.[2]

QM provides a framework for interpreting inter­ventions because of the unique perspective it offers on the nature of particles. In QM, particles are not simply located in one point of space. Instead of be­ing in a single point in space, a particle is essentially “spread” throughout all space. However, the parti­cle is not evenly spread throughout all space. That is, there are some locations with a “thicker” spread of the particle, and other locations with a “thinner” spread of the particle.

But then, why do objects look like they are in one place? This is because by observing the object, one takes a measurement of that object’s location. Or rather, one takes a measurement of the particles composing the object. When a measurement of a particle’s location is taken, the particle “chooses” a point in space and appears there. That is, after a measurement, the spread of a particle “collapses” to a single point in space.

With this in mind: What does it mean for the spread of a particle to be thicker or thinner at certain points in space? Basically, the thicker the spread at a certain location, the more likely the particle will choose to collapse there after a measurement. So, the thickness of the spread of a particle basically shows where the particle will likely collapse after a measurement.

Another important question: How often do par­ticles choose where to collapse? According to one theory, the Ghirardi-Rimini-Weber (GRW) interpre­tation of QM, “a macroscopic [system] undergoes a [measurement] every 10-7 seconds.”[3] This means that the particles in ordinary objects are measured, then spread out a little, then 10-7 seconds later are measured again, and this cycle repeats.[4] Since ordi­nary objects are composed of multiple particles, this process occurs for each particle. Let us refer to the set of locations to which the particles of an object collapse as the “collapse-outcome” of the measure­ment.

What determines the collapse-outcome of a measurement of an object? In most cases, there is an extremely high probability that the collapse-outcome of an object will result in ordinary behavior. Howev­er, it is technically possible for the collapse-outcome to result in weird behavior. For example, the col­lapse-outcome of a rock at rest will most likely leave the rock at rest. But there is a miniscule chance that all the particles in the rock will choose to collapse in another galaxy. Extremely unlikely? Yes. But still possible.

This is where intervention becomes relevant. According to Plantinga, it is possible that God deter­mines every collapse-outcome for most particles.[5] In this way God can control the physical reality and intervene when he desires, all in a way that is con­sistent with science. With this framework of QM, concepts like miracles and free will can now be an­alyzed.

Rethinking Miracles

How can we define a miracle with a quantum me­chanical perspective? Classically, a miracle is an event that defies the laws of nature that humans have constructed. But when considering QM, inter­vention does not (in any obvious way) defy the laws of nature. Plantinga states that it is possible that some events, “…while not flatly excluded by QM, are so improbable (given QM) that they wouldn’t be ex­pected to occur in a period 1010 times the age of the universe. Such [an event], if it were to occur (and if we were to think of QM as universally applicable), would disconfirm QM; it would be evidence against QM…” 6So if an event occurs that is so radically improbable that the most likely explanation is that QM is incorrect, then perhaps such an event can be classified as a miracle.

Plantinga explains that when such an improba­ble event occurs, “…God is treating his world differ­ently from the way in which he ordinarily treats it; but the laws of nature, including QM, should be thought of as descriptions of the material universe when God is not treating what he has made in a special way.”[7] Hence, a miracle can alternatively be defined as when God treats the universe differently than he normally does. And QM shows that God can do this without blatantly defying the laws of nature.

Explaining Free Will

God’s control over collapse-outcomes may initial­ly appear to be evidence against free will, or even seem to entail occasionalism.[8] To counter this, Plantinga argues that it is still possible for free will to exist by making a qualification. Consider the doc­trine that humans have an immaterial part of them, the soul. Then perhaps the human soul can con­trol certain collapse-outcomes, but only for particles in their own physical brain. This way humans can express their will through their own brain, and thus their body as well. Meanwhile, God still controls all other collapse-outcomes. Then, as Plantinga puts it, “God sets the stage for such free action by caus­ing a world of regularity and predictability; but he causes only some of the collapse-outcomes, leav­ing it to the free persons to cause the rest.”[9] Thus, this QM analysis does not pose any threat to free will, but instead can be used to rationalize free will. Additionally, this discussion of miracles and the hu­man free will can easily be extended to other free agents like angels and demons. When such beings interface with physical reality, they determine the collapse-outcomes of certain particles.

Note that this analysis assumes that God deter­mines the collapse-outcomes of all particles other than those controlled by free agents. In this way God himself upholds the patterns of nature we observe, but is not constrained to holding those patterns, so he can break them whenever he wishes. Hence, this assumption allows interventions to exist without breaking any absolute “laws of nature.” However, this assumption is not necessarily true, and it is still possible that miracles do violate the laws of nature. But even in this case intervention is still plausible, as Plantinga makes an argument for its plausibility using classical mechanics in his work Where the Conflict Really Lies.

Conclusion

By considering miracles in a quantum mechanical perspective, one can acknowledge spiritual interac­tions without defying any scientific principles. How­ever, as Plantinga states, although it is nice to find such a framework, Christians are “…not obliged to trim [their] sails to the current scientific breeze on the topic, revising [their] belief on the topic every time science changes its mind…”[10] Scientific knowledge changes and evolves over time, but the claims of Christianity are meant to be eternally true. Some­day QM may be replaced with a superior theory, but the foundational tenets of Christianity will remain the same, and there is merit in believing Christian claims outside of science. But at least in the moment we can rest assured that there is no irreconcilable rift between modern science and intervention.

2 Although Plantinga argues for the consistency of science and inter­vention under QM, he also previously argued for the consistency under classical, deterministic mechanics. Hence, the consistency of science and intervention does not hinge on QM; but the development of QM offers yet another way to reconcile science and intervention.

3 Quoted from Plantinga, Where the Conflict Really Lies, 115.

4 Note that the GRW is one of many philosophical interpretations of QM. But this interpretation is not the scientific consensus. However, it is still plausible and in theory is testable.

5 Plantinga, Where the Conflict Really Lies, 116.

6 Quoted from Plantinga, Where the Conflict Really Lies, 118.

7 Quoted from Plantinga, Where the Conflict Really Lies, 119.

8 Occasionalism is the theory that God completely and directly causes every event that occurs.

9 Quoted from Plantinga, Where the Conflict Really Lies, 120.

10 Quoted from Plantinga, Where the Conflict Really Lies, 121.

Ronald graduated in 2018 with a B.S. in Electrical Engineering and Physics. He is from New Mexico and enjoys philosophy, theology, tennis, and video games. He does research in the quantum nanopho­tonics group at MIT.